We find that the performance gap in terms of class dropout and pass rates between white and minority students falls by roughly half when taught by a minority instructor. In models that allow for a full set of ethnic and racial interactions between students and instructors, we find African-American students perform particularly better when taught by African-American instructors. . . . The class dropout rate relative to Whites is 6 percentage points lower for Black students when taught by a Black instructor. Conditional on completing the course, the relative fraction attaining a B-average or greater is 13 percentage points higher.

The paper’s authors — Robert Fairlie, Florian Hoffmann and Philip Oreopoulos — conclude that this effect is due to minority students’ positive reactions to minority teachers — what other researchers have dubbed the “role-model effect”:

First, we find dropout effects from instructor race and ethnicity prior to receiving grades. This outcome is entirely determined by the student rather than the instructor. Second, as shown in table 4, it is the young students who are most affected by the instructor’s minority status . . . young students are likely to be susceptible to role-model effects, while older students are not.

As a side note, the researchers point out that only 9.6 percent of all full-time faculty members at U.S. colleges are black, Latino or Native American, while those groups compose one-third of the entire college-age population.